Afshon Ostovar is a senior analyst at the Center for Naval Analyses, and he's writing a book about Iran's Revolutionary Guards. He says the force was originally established after the Iran-Iraq war.

"It absorbed a portfolio that Iran had already cultivated during the '80s, in which Iran would operate in places like Iraq or Afghanistan, but especially in Lebanon, to help other militant organizations advance their causes," he said on today's Talk of the Nation. In Lebanon, that meant the Palestinians, and then the Lebanese Shia under Hezbollah.

But after the Iran-Iraq war, it became more of a military division that focused on promoting Iran's strategy outside of its borders. "In this way, working with militant gropus in Iraq or Lebanon was less to advance [Lebanese or Iraqi] causes, but rather to advance the causes of Tehran."

It's a covert organization, he says, and has the architecture of an intelligence organization like the CIA. But it operates more like the U.S. special forces. "They work alongside foreign groups to help train, help facilitate, help with logistics and help with funding. However, they don't get their hands dirty directly, they try to have plausible deniability in everything that they do. They're more about facilitating others than doing things themselves."

The Quds Force also reports directly to supreme leader Ayatollah Ali Khamenei, not President Mahmoud Ahmadinejad. "Our understanding is even though they are technically one of the five divisions of the Revolutionary Guards ... their leadership circumvents that of the Revolutionary Guards and goes directly to the supreme leader." In that way, the Quds Force "operates as a direct arm of the supreme leader's foreign policy."

Though the Quds Force is involved in violent activities around the world, "this is ... drastically out of step with their modus operandi," said Ostovar. Though it's outside Iran's borders — which is their assignment — and involves assassination, which is in line with what they do, "for them to do it in the United States is unprecedented." And to work with the Mexican cartels is also unprecedented, as far as anyone knows. "They do have long-established connections with Chavez in Venezuela and other Central American groups, but not with the Mexicans."

And as for the Iranian expatriate who seems to have been the middle man, Manssor Arbabsiar, "that really just doesn't fit what they usually do." They usually work with well-vetted, well-trusted intermediaries. "To simply have a commander's cousin that happens to live in Texas and ask him to put these things together just doesn't fit."

For more on what Ostovar thinks about the plot, there's a piece he's written for Foreign Policy titled "Worst. Plot. Ever."

Vali Nasr, professor of international politics at Tufts University's Fletcher School of Law and Diplomacy, said during the broadcast that the evidence that's been made public is a bit obscure. We know quite a bit about what seems to have happened in the U.S., but "when the thread goes from the United States and Mexico to Iran, it becomes far less clear as to where it leads." He hasn't yet seen compelling evidence that pinpoints to whom in Iran Arbabsiar was in contact with and who made the decision in Iran, if indeed it came from there.

"The Quds Force is a fairly disciplined organization that executes policies that are decided by Iran's political leadership," Nasr said. "We don't have an example of the Quds Force having gone rogue ... But again, it's not clear as to who exactly in Iran made this order."

As we reported earlier, President Obama said today that he's confident the evidence shows "that an individual of Iranian-American descent was involved in a plot to assassinate the ambassador to the United States from Saudi Arabia, and we also know that he had direct links, was paid by and directed by individuals in the Iranian government."

Iran has rejected such allegations.

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